The copyright protection of digital content became a critical issue now a days. Digital image watermarking is one of the techniques used to protect digital content. A novel image watermarking approach based on back propagation neural network in DWT domain is proposed in this paper. The cover image is decomposed up to 3-levels using DWT. The bitmap is selected as a watermark. The back propagation neural network is implemented while embedding and extracting the watermark. The proposed watermarking algorithm is imperceptible and robust to some normal attacks such as JPEG compression, salt and pepper noise, rotation and cropping.